Process for bleaching articles.



UNITED v STATES PATENT OFFICE.

AUGUSTE J. ROSSI, OF NIAGARA FALLS, NEW YORK, AS SIGNOB TO THE TITANIUMALLOY MANUFACTURING COMPANY, OF NEW YORK, N. Y., A CORPORATION OF MAINE.

PROCESS FOR BLEACHING ARTICLES.

1,080,718. Specification of Letters Patent.

No Drawingi To all whom it may concern:

Be it known that I, AUGUST-E J. -Ross1, 'a citizen of the United States,and a resident of Niagara Falls, in the county of Niagara and State ofNew York, have invented certain new and useful Improvements in Processesfor Bleachin- Articles, of which the following is a specification.

My present invention relates to what is broadly termed bleaching,including the discharging from fabrics of undesired natural orartificial coloring matters or pig origin, silk for instance, rendersits use thereon hazardous and In mostcases unde f sirable or impossible.

The use of sulfur dioxid for bleaching is also, in many instances, far'from satis tory, some fabrics treated therewith, particularly thosepreviously dyed, coming out less urely white than is desirable, andshowing off, when ironed, too many traces of their original colors.

By the cautious and skilful use of certain well known bleaching powders,such for instance as depend largely on chlorin liberated fromhypochlorites, better results are often obtained, but the presence ofsuch chlorin causes such deterioration in the fiber and appearance ofthe silken portions of' the fabric as to cause loss to the manufacturer.

I have long shared with others the conception that chlorid of titaniummight possibly be used with advantage as a substitute for v theaforesaid bleaching agents, and have experimented in hopes of realizingthis.

roduced the tetrachlorid of ti-' To this end I tanium, Ti 1,, by thewell known method which consists in passing chlorin gas over .a mixtureof carbon and titanic acid heated to redness, thereby obtaining ayellowish liquid Patented Dec. 9, 191 3.

Application filed January 31, 1912. Serial No. 674,544. i

smelling strongly of chlorin because contaming free chlorin in solution.On applying this solution experimentally to some textiles, I found thembleached to an ex vegetable origin, such as cotton, etc. I resorted nextto well known methods by which I was enabled to eliminate free chlorintherefrom to an extent. On applying the solution thus freed I found thatit had no bleaching effect, from which I infer that the scribed, ableaching agent uninjurious to animal substances such as silks, orwool,etc., whether in raw condition, or manufactured as textiles, etc.

My said solution containing the desired sesquichlorid of titanium in anyrequired amount may be economically and readily produced by dissolving,in hydrochloric acid at normal temperature, an alloy of iron andtitanium commonly known as ferro-titanium. The said solution so producedis exceptionally well adapted to bleaching purposes, not only because ofits said content of said sesquichlorid, but also because of absencetherefrom of free chlorin injurious to animal substances, this being dueto its content of ferrous chlorid which is not only itself non-injuriousbut also contributes to the stability of the solution.

I produce said solution as follows :In a vessel lined preferably withporcelain or like resistant material, I dissolve, at below boilingtemperature, in hydrochloric acid dibatedwith its weight of water orless, an alloy of iron and titanium as high, in titanium as desired, forexample the alloy for which were granted to me Letters Patent No.648,439, dated May 1, 1900. The resuiting liquor should be of a violetcolor,

tanium has been formed. I next filter the liquor to remove therefromsuch small quantities of silica, carbon, or other impurities, includingthe titanium oxid which should be formed but to a small extent. Ordinaryfil-- ter presses, or any other similar contrivances, can be used withadvantage for this pur ose. The liquid thus filtered is then rea y foruse.

As will be readily understood by those skilled in the art, therespective proportions of the respective ingredients of the charge inproducing said solution will depend upon the respective ascertainedcharacteristics and proportions of each; that is to say the amount bweight of commercial hydrochloric acid charged will, in each case,depend upon its HCl content and upon the amount of-the latter requiredto satisfy the respective chemical aflinlties therefor of all the ironand titanium in the charge.

Careful tests have demonstrated that the presence of the chlorid of ironinterferes in no respect with the bleaching properties of my saidsolution, these being exceptionally perfect, and non-injurious to thematerials of animal origin to which applied; also that it ischaracterized as containing substantially no free chlorin; also thatit-is very notably stable as compared with previous solutions containingcompounds of chlorin. Its chlorids appear to part with their chlorinonly in proportion as the bleaching proceeds, and when sufficientlyproximate to the coloring matter with which it promptly 'combines, thusprecluding the presence of free chlorin in the solution at any stage.This comparative stability of my solution seems attributable only to itscontent of ferrous chlorid which principally distinguishes it from allprevious solutions containing titanous chlorids, for example such. ashave heretofore been suggested as able. to discharge color from fabrics.It seemsv that the titanous chlorids of such previous solutions have,owing to their nature and environment, proved too, if not prohibitorily,unstable, their titanium content tending to separate and combine withoxygen resent to form titanic acid, thus prohibitorily liberating in thesolution free chlorin to injure animal substances if thereby treated;whereas, in my said novel solution, such free chlorin if any soliberated combines promptly with the ferrous chlorid present to formferric chlorid, whereby free chlorin is sub stantially prevented fromreachin and deterioratin the bleaching animal filiers, such as that osilk, which would otherwise be ruined thereby.

The methods of applying my said solution tothe materials treated therebywill of course be readily understood by those skilled in the bleachingart. The violet solution is of course diluted with water to meet thespecial requlrements of the particular materials or particular dyestherein contained,

such dilution causing the violet color to assume lighter shades inproportion to the water added. Should the solution in any case prove toostrongly acid, its acidity may be counteracted by additions of anyproper alkali, such as ammonia for example. To avoid injury to thematerials it is of course preferable that the solution employed shouldbe but slightly acid. The solution will be applied to; the materialstreated in substantially the same way as any other solution employed forbleaching purposes. Such methods of application are too well understoodto require description here. For instance the usual bleaching vats areemployed, the solution charged thereinto and the materials soakedtherein as usual, or the solution may be otherwise applied in anyconvenient manner. The temperatures employed will depend upon thepreference and experience of the individual operators. Normaltemperatures involve longer exposure to the solution and highertemperatures shorterexposure as will be well understood. It ispreferable to avoid boiling temperature except in cases in which thesolution is very considerably diluted. It goes without saying that thefabrics, after application thereto of the solution, are thoroughlywashed, etc., according to the usual procedure of the art.

Applications of my said bleaching solution, derived as aforesaid from aniron titanium alloy containing about 16 per cent. titanium, made to acotton fabric of-slightly lavender color containing stripes of silk of adeeper shade ave the following results. Said fabric, boiled ,in my saidsolution diluted ten times with water to meet the special requirementsof this particular fabric was rapidly bleached a ure white,notwithstanding which the brilliancy of the 511k stripes was unimpaired.Other specimens of the same fabric, treated as usual with sulfur dioxidsolutions emerged not comletely bleached, the white having a grayishBlue hue prohibiting the use thereof as a white fabric 'and'ob'ectionable for dyeing in certain delicate li t colors. Otherspecimens of the same abrics treated as usual with chlorin, or bleachi'npowders, above referred to, presented a eteriorated appearance, and,thou h nearer to pure white their silk stripes ha lost much of theiroriginal brilliancy. 1

It is preferable in my experience that the ferro-titanium employedshould contain not less than 16 per cent. of titanium,'and be dissolvedas aforesaid in hydrochloric'acid diluted by about its own weight ofwater to produce, prior to further ilution for use,

an initial solution containing not less than about 25 per cent. of thesesquichlorid of titanium.

Maintenance of the bath at substantially normal, 5. 6. below boiling,temperature is, I have discovered, essential in order to produce thedesired sesquichlorid of titanium from the ferro-titanium treated underthe conditions mentioned. My experiments have demonstrated that if thetemperature of the bath rises to approximately, or above, boiling, thetitanium content goes to make titanium oxid, more or less precipitated,which, like other compounds of titanium except the sesquichlorid,appears unable to bleach, as desired, the fabric or other materialtreated, thus Wasting the chlorin content notwithstanding surplus freechlorin so liberated is promptly taken up by the ferrous chlorid presentas aforesaid.

It will of course be understood that my said method, and my solutioncontaining both titanous and ferrous chlorids, are equivalentlyapplicable, as above described, to not onl bleachin specifically, butalso to the discharging of colors previously artificially applied, andalso to the restoring of colors. In each of these applications thereducing action of the titanous chlorid is similarly relied upon; 1'. e.in bleaching it deoxidizes as required to improve the appearance of thefabric wherever it has been undesirably affected by oxidizing agents; indischarging, it also deoxidizes to remove. the color rom previouslyapplied artificial dyes; in restoring, it also deoxidizes to restoreoriginal color to portions of the fabric which, by reason of previousfinishing or bleaching treatments, have been unduly oxidized andconsequently dimmed or altered.

What I claim as new and desire to secure by Letters Patent is thefollowing, viz

1. The method of bleaching materials which comprises applying thereto asolution containing sesquichlorid of titanium (Ti Cl and ferrouschlorid.

2. The method of bleaching materials which comprises applyin thereto asolution containing titanous chTorid and ferrous chlorid.

3. The method of bleaching materials which comprises dissolving titaniumand iron in dilute hydrochloric acid, filtering the resulting solution,and applying it to said material.

4. The method of bleaching materials which comprises dissolving an alloyof iron and titaniumin dilute h drochloric acid, filtering the resultingsolution, and applying it to the said material.

5. The method of bleaching materials which comprises dissolvin in dilutehydrocloric acid at below norma boiling temperature an alloy of iron andtitanium, filtering the resulting liquor to remove therefrom impuritiesincluding titanium oxid, and carbon, and then applying it to saidmaterials.

6. The method which comprises dissolving titanium and iron in dilutehydrochloric acid at below normal boiling temperature, filtering theresulting liquor to remove therefrom impurities including titanium oxid,and carbon, and then applying it to said materials.

AUGUSTE J. ROSSI.

Witnesses:

WALTER D. EDWARDS, PHILIP G. Pnox.

of bleaching materials

